Граф коммитов

123 Коммитов

Автор SHA1 Сообщение Дата
Andrey Konovalov 80b92bfe3b kasan: dynamically allocate stack ring entries
Instead of using a large static array, allocate the stack ring dynamically
via memblock_alloc().

The size of the stack ring is controlled by a new kasan.stack_ring_size
command-line parameter.  When kasan.stack_ring_size is not provided, the
default value of 32 << 10 is used.

When the stack trace collection is disabled via kasan.stacktrace=off, the
stack ring is not allocated.

Link: https://lkml.kernel.org/r/03b82ab60db53427e9818e0b0c1971baa10c3cbc.1662411800.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:02 -07:00
Andrey Konovalov 7ebfce3312 kasan: support kasan.stacktrace for SW_TAGS
Add support for the kasan.stacktrace command-line argument for Software
Tag-Based KASAN.

The following patch adds a command-line argument for selecting the stack
ring size, and, as the stack ring is supported by both the Software and
the Hardware Tag-Based KASAN modes, it is natural that both of them have
support for kasan.stacktrace too.

Link: https://lkml.kernel.org/r/3b43059103faa7f8796017847b7d674b658f11b5.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:01 -07:00
Andrey Konovalov 7bc0584e5d kasan: implement stack ring for tag-based modes
Implement storing stack depot handles for alloc/free stack traces for slab
objects for the tag-based KASAN modes in a ring buffer.

This ring buffer is referred to as the stack ring.

On each alloc/free of a slab object, the tagged address of the object and
the current stack trace are recorded in the stack ring.

On each bug report, if the accessed address belongs to a slab object, the
stack ring is scanned for matching entries.  The newest entries are used
to print the alloc/free stack traces in the report: one entry for alloc
and one for free.

The number of entries in the stack ring is fixed in this patch, but one of
the following patches adds a command-line argument to control it.

[andreyknvl@google.com: initialize read-write lock in stack ring]
  Link: https://lkml.kernel.org/r/576182d194e27531e8090bad809e4136953895f4.1663700262.git.andreyknvl@google.com
Link: https://lkml.kernel.org/r/692de14b6b6a1bc817fd55e4ad92fc1f83c1ab59.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:01 -07:00
Andrey Konovalov 59e6e098d1 kasan: introduce kasan_complete_mode_report_info
Add bug_type and alloc/free_track fields to kasan_report_info and add a
kasan_complete_mode_report_info() function that fills in these fields. 
This function is implemented differently for different KASAN mode.

Change the reporting code to use the filled in fields instead of invoking
kasan_get_bug_type() and kasan_get_alloc/free_track().

For the Generic mode, kasan_complete_mode_report_info() invokes these
functions instead.  For the tag-based modes, only the bug_type field is
filled in; alloc/free_track are handled in the next patch.

Using a single function that fills in these fields is required for the
tag-based modes, as the values for all three fields are determined in a
single procedure implemented in the following patch.

Link: https://lkml.kernel.org/r/8432b861054fa8d0cee79a8877dedeaf3b677ca8.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:01 -07:00
Andrey Konovalov 7fae3dd08e kasan: fill in cache and object in complete_report_info
Add cache and object fields to kasan_report_info and fill them in in
complete_report_info() instead of fetching them in the middle of the
report printing code.

This allows the reporting code to get access to the object information
before starting printing the report.  One of the following patches uses
this information to determine the bug type with the tag-based modes.

Link: https://lkml.kernel.org/r/23264572cb2cbb8f0efbb51509b6757eb3cc1fc9.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:01 -07:00
Andrey Konovalov 015b109f1f kasan: introduce complete_report_info
Introduce a complete_report_info() function that fills in the
first_bad_addr field of kasan_report_info instead of doing it in
kasan_report_*().

This function will be extended in the next patch.

Link: https://lkml.kernel.org/r/8eb1a9bd01f5d31eab4524da54a101b8720b469e.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:00 -07:00
Andrey Konovalov 559756e8a2 kasan: make kasan_addr_to_page static
As kasan_addr_to_page() is only used in report.c, rename it to
addr_to_page() and make it static.

Link: https://lkml.kernel.org/r/66c1267200fe0c16e2ac8847a9315fda041918cb.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:03:00 -07:00
Andrey Konovalov 6b07434980 kasan: pass tagged pointers to kasan_save_alloc/free_info
Pass tagged pointers to kasan_save_alloc/free_info().

This is a preparatory patch to simplify other changes in the series.

Link: https://lkml.kernel.org/r/d5bc48cfcf0dca8269dc3ed863047e4d4d2030f1.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:02:59 -07:00
Andrey Konovalov be95e13fcc kasan: only define metadata structs for Generic mode
Hide the definitions of kasan_alloc_meta and kasan_free_meta under an
ifdef CONFIG_KASAN_GENERIC check, as these structures are now only used
when the Generic mode is enabled.

Link: https://lkml.kernel.org/r/8d2aabff8c227c444a3f62edf87d5630beb77640.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:02:59 -07:00
Andrey Konovalov 5935143d11 kasan: introduce kasan_init_cache_meta
Add a kasan_init_cache_meta() helper that initializes metadata-related
cache parameters and use this helper in the common KASAN code.

Put the implementation of this new helper into generic.c, as only the
Generic mode uses per-object metadata.

Link: https://lkml.kernel.org/r/a6d7ea01876eb36472c9879f7b23f1b24766276e.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:02:58 -07:00
Andrey Konovalov 284f8590a1 kasan: introduce kasan_requires_meta
Add a kasan_requires_meta() helper that indicates whether the enabled
KASAN mode requires per-object metadata and use this helper in the common
code.

Also hide kasan_init_object_meta() under CONFIG_KASAN_GENERIC ifdef check,
as Generic is the only mode that uses per-object metadata.

To allow for a potential future change that makes Generic KASAN support
the kasan.stacktrace command-line parameter, let kasan_requires_meta()
return kasan_stack_collection_enabled() instead of simply returning true.

Link: https://lkml.kernel.org/r/cf837e9996246aaaeebf704ccf8ec26a34fcf64f.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:02:58 -07:00
Andrey Konovalov 2f35680172 kasan: move kasan_get_*_meta to generic.c
Move the implementations of kasan_get_alloc/free_meta() to generic.c, as
the common KASAN code does not use these functions anymore.

Also drop kasan_reset_tag() from the implementation, as the Generic mode
does not tag pointers.

Link: https://lkml.kernel.org/r/ffcfc0ad654d78a2ef4ca054c943ddb4e5ca477b.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:02:57 -07:00
Andrey Konovalov 836daba099 kasan: introduce kasan_init_object_meta
Add a kasan_init_object_meta() helper that initializes metadata for a slab
object and use it in the common code.

For now, the implementations of this helper are the same for the Generic
and tag-based modes, but they will diverge later in the series.

This change hides references to alloc_meta from the common code.  This is
desired as only the Generic mode will be using per-object metadata after
this series.

Link: https://lkml.kernel.org/r/47c12938fc7f8105e7aaa592527c0e9d3c81fc37.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:02:57 -07:00
Andrey Konovalov f3647cbfe5 kasan: introduce kasan_get_alloc_track
Add a kasan_get_alloc_track() helper that fetches alloc_track for a slab
object and use this helper in the common reporting code.

For now, the implementations of this helper are the same for the Generic
and tag-based modes, but they will diverge later in the series.

This change hides references to alloc_meta from the common reporting code.
This is desired as only the Generic mode will be using per-object
metadata after this series.

Link: https://lkml.kernel.org/r/0c365a35f4a833fff46f9d42c3212b32f7166556.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:02:57 -07:00
Andrey Konovalov 88f29765ae kasan: introduce kasan_print_aux_stacks
Add a kasan_print_aux_stacks() helper that prints the auxiliary stack
traces for the Generic mode.

This change hides references to alloc_meta from the common reporting code.
This is desired as only the Generic mode will be using per-object
metadata after this series.

Link: https://lkml.kernel.org/r/67c7a9ea6615533762b1f8ccc267cd7f9bafb749.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:02:57 -07:00
Andrey Konovalov 687c85afa6 kasan: drop CONFIG_KASAN_TAGS_IDENTIFY
Drop CONFIG_KASAN_TAGS_IDENTIFY and related code to simplify making
changes to the reporting code.

The dropped functionality will be restored in the following patches in
this series.

Link: https://lkml.kernel.org/r/4c66ba98eb237e9ed9312c19d423bbcf4ecf88f8.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:02:57 -07:00
Andrey Konovalov ccf643e6da kasan: split save_alloc_info implementations
Provide standalone implementations of save_alloc_info() for the Generic
and tag-based modes.

For now, the implementations are the same, but they will diverge later in
the series.

Link: https://lkml.kernel.org/r/77f1a078489c1e859aedb5403f772e5e1f7410a0.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:02:56 -07:00
Andrey Konovalov c249f9af85 kasan: rename kasan_set_*_info to kasan_save_*_info
Rename set_alloc_info() and kasan_set_free_info() to save_alloc_info() and
kasan_save_free_info().  The new names make more sense.

Link: https://lkml.kernel.org/r/9f04777a15cb9d96bf00331da98e021d732fe1c9.1662411799.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-10-03 14:02:56 -07:00
Kuan-Ying Lee 3de0de7580 kasan: separate double free case from invalid free
Currently, KASAN describes all invalid-free/double-free bugs as
"double-free or invalid-free".  This is ambiguous.

KASAN should report "double-free" when a double-free is a more likely
cause (the address points to the start of an object) and report
"invalid-free" otherwise [1].

[1] https://bugzilla.kernel.org/show_bug.cgi?id=212193

Link: https://lkml.kernel.org/r/20220615062219.22618-1-Kuan-Ying.Lee@mediatek.com
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Yee Lee <yee.lee@mediatek.com>
Cc: Andrew Yang <andrew.yang@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-07-17 17:14:33 -07:00
Andrey Konovalov 06bc4cf6cd kasan: give better names to shadow values
Rename KASAN_KMALLOC_* shadow values to KASAN_SLAB_*, as they are used for
all slab allocations, not only for kmalloc.

Also rename KASAN_FREE_PAGE to KASAN_PAGE_FREE to be consistent with
KASAN_PAGE_REDZONE and KASAN_SLAB_FREE.

Link: https://lkml.kernel.org/r/bebcaf4eafdb0cabae0401a69c0af956aa87fcaa.1652111464.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-13 07:20:19 -07:00
Andrey Konovalov 83f8e4a8b4 kasan: use tabs to align shadow values
Consistently use tabs instead of spaces to shadow value definitions.

Link: https://lkml.kernel.org/r/00e7e66b5fc375d58200dc1489949b3edcd096b7.1652111464.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-13 07:20:18 -07:00
Andrey Konovalov fc0e5b91df kasan: clean up comments in internal kasan.h
Clean up comments in mm/kasan/kasan.h: clarify, unify styles, fix
punctuation, etc.

Link: https://lkml.kernel.org/r/a0680ff30035b56cb7bdd5f59fd400e71712ceb5.1652111464.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
2022-05-13 07:20:18 -07:00
Vincenzo Frascino b1add418d4 kasan: fix hw tags enablement when KUNIT tests are disabled
Kasan enables hw tags via kasan_enable_tagging() which based on the mode
passed via kernel command line selects the correct hw backend.
kasan_enable_tagging() is meant to be invoked indirectly via the cpu
features framework of the architectures that support these backends.
Currently the invocation of this function is guarded by
CONFIG_KASAN_KUNIT_TEST which allows the enablement of the correct backend
only when KUNIT tests are enabled in the kernel.

This inconsistency was introduced in commit:

  ed6d74446c ("kasan: test: support async (again) and asymm modes for HW_TAGS")

... and prevents to enable MTE on arm64 when KUNIT tests for kasan hw_tags are
disabled.

Fix the issue making sure that the CONFIG_KASAN_KUNIT_TEST guard does not
prevent the correct invocation of kasan_enable_tagging().

Link: https://lkml.kernel.org/r/20220408124323.10028-1-vincenzo.frascino@arm.com
Fixes: ed6d74446c ("kasan: test: support async (again) and asymm modes for HW_TAGS")
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-04-15 14:49:55 -07:00
Andrey Konovalov 80207910cd kasan: move and hide kasan_save_enable/restore_multi_shot
- Move kasan_save_enable/restore_multi_shot() declarations to
   mm/kasan/kasan.h, as there is no need for them to be visible outside
   of KASAN implementation.

 - Only define and export these functions when KASAN tests are enabled.

 - Move their definitions closer to other test-related code in report.c.

Link: https://lkml.kernel.org/r/6ba637333b78447f027d775f2d55ab1a40f63c99.1646237226.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:50 -07:00
Andrey Konovalov c965cdd675 kasan: rename kasan_access_info to kasan_report_info
Rename kasan_access_info to kasan_report_info, as the latter name better
reflects the struct's purpose.

Link: https://lkml.kernel.org/r/158a4219a5d356901d017352558c989533a0782c.1646237226.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:50 -07:00
Andrey Konovalov 31c65110b9 kasan: call print_report from kasan_report_invalid_free
Call print_report() in kasan_report_invalid_free() instead of calling
printing functions directly.  Compared to the existing implementation of
kasan_report_invalid_free(), print_report() makes sure that the buggy
address has metadata before printing it.

The change requires adding a report type field into kasan_access_info and
using it accordingly.

kasan_report_async() is left as is, as using print_report() will only
complicate the code.

Link: https://lkml.kernel.org/r/9ea6f0604c5d2e1fb28d93dc6c44232c1f8017fe.1646237226.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:49 -07:00
Andrey Konovalov 9d7b7dd946 kasan: split out print_report from __kasan_report
Split out the part of __kasan_report() that prints things into
print_report().  One of the subsequent patches makes another error handler
use print_report() as well.

Includes lower-level changes:

 - Allow addr_has_metadata() accepting a tagged address.

 - Drop the const qualifier from the fields of kasan_access_info to
   avoid excessive type casts.

 - Change the type of the address argument of __kasan_report() and
   end_report() to void * to reduce the number of type casts.

Link: https://lkml.kernel.org/r/9be3ed99dd24b9c4e1c4a848b69a0c6ecefd845e.1646237226.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:49 -07:00
Andrey Konovalov 49d9977ac9 kasan: check CONFIG_KASAN_KUNIT_TEST instead of CONFIG_KUNIT
Check the more specific CONFIG_KASAN_KUNIT_TEST config option when
defining things related to KUnit-compatible KASAN tests instead of
CONFIG_KUNIT.

Also put the kunit_kasan_status definition next to the definitons of other
KASAN-related structs.

Link: https://lkml.kernel.org/r/223592d38d2a601a160a3b2b3d5a9f9090350e62.1646237226.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:49 -07:00
Andrey Konovalov 1e0f611fab kasan: print basic stack frame info for SW_TAGS
Software Tag-Based mode tags stack allocations when CONFIG_KASAN_STACK
is enabled. Print task name and id in reports for stack-related bugs.

[andreyknvl@google.com: include linux/sched/task_stack.h]
  Link: https://lkml.kernel.org/r/d7598f11a34ed96e508f7640fa038662ed2305ec.1647099922.git.andreyknvl@google.com

Link: https://lkml.kernel.org/r/029aaa87ceadde0702f3312a34697c9139c9fb53.1646237226.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:49 -07:00
Andrey Konovalov ed6d74446c kasan: test: support async (again) and asymm modes for HW_TAGS
Async mode support has already been implemented in commit e80a76aa1a
("kasan, arm64: tests supports for HW_TAGS async mode") but then got
accidentally broken in commit 99734b535d ("kasan: detect false-positives
in tests").

Restore the changes removed by the latter patch and adapt them for asymm
mode: add a sync_fault flag to kunit_kasan_expectation that only get set
if the MTE fault was synchronous, and reenable MTE on such faults in
tests.

Also rename kunit_kasan_expectation to kunit_kasan_status and move its
definition to mm/kasan/kasan.h from include/linux/kasan.h, as this
structure is only internally used by KASAN.  Also put the structure
definition under IS_ENABLED(CONFIG_KUNIT).

Link: https://lkml.kernel.org/r/133970562ccacc93ba19d754012c562351d4a8c8.1645033139.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:48 -07:00
Andrey Konovalov 551b2bcb7e kasan: add kasan.vmalloc command line flag
Allow disabling vmalloc() tagging for HW_TAGS KASAN via a kasan.vmalloc
command line switch.

This is a fail-safe switch intended for production systems that enable
HW_TAGS KASAN.  In case vmalloc() tagging ends up having an issue not
detected during testing but that manifests in production, kasan.vmalloc
allows to turn vmalloc() tagging off while leaving page_alloc/slab
tagging on.

Link: https://lkml.kernel.org/r/904f6d4dfa94870cc5fc2660809e093fd0d27c3b.1643047180.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:48 -07:00
Andrey Konovalov 241944d162 kasan: clean up feature flags for HW_TAGS mode
- Untie kasan_init_hw_tags() code from the default values of
   kasan_arg_mode and kasan_arg_stacktrace.

 - Move static_branch_enable(&kasan_flag_enabled) to the end of
   kasan_init_hw_tags_cpu().

 - Remove excessive comments in kasan_arg_mode switch.

 - Add new comments.

Link: https://lkml.kernel.org/r/76ebb340265be57a218564a497e1f52ff36a3879.1643047180.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:48 -07:00
Andrey Konovalov 00a756133b kasan: define KASAN_VMALLOC_INVALID for SW_TAGS
In preparation for adding vmalloc support to SW_TAGS KASAN, provide a
KASAN_VMALLOC_INVALID definition for it.

HW_TAGS KASAN won't be using this value, as it falls back onto page_alloc
for poisoning freed vmalloc() memory.

Link: https://lkml.kernel.org/r/1daaaafeb148a7ae8285265edc97d7ca07b6a07d.1643047180.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Acked-by: Marco Elver <elver@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:47 -07:00
Andrey Konovalov fe1ac91edb kasan: clean up metadata byte definitions
Most of the metadata byte values are only used for Generic KASAN.

Remove KASAN_KMALLOC_FREETRACK definition for !CONFIG_KASAN_GENERIC case,
and put it along with other metadata values for the Generic mode under a
corresponding ifdef.

Link: https://lkml.kernel.org/r/ac11d6e9e007c95e472e8fdd22efb6074ef3c6d8.1643047180.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Acked-by: Marco Elver <elver@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2022-03-24 19:06:47 -07:00
Matthew Wilcox (Oracle) 6e48a966df mm/kasan: Convert to struct folio and struct slab
KASAN accesses some slab related struct page fields so we need to
convert it to struct slab. Some places are a bit simplified thanks to
kasan_addr_to_slab() encapsulating the PageSlab flag check through
virt_to_slab().  When resolving object address to either a real slab or
a large kmalloc, use struct folio as the intermediate type for testing
the slab flag to avoid unnecessary implicit compound_head().

[ vbabka@suse.cz: use struct folio, adjust to differences in previous
  patches ]

Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Tested-by: Hyeongogn Yoo <42.hyeyoo@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: <kasan-dev@googlegroups.com>
2022-01-06 12:26:14 +01:00
Linus Torvalds 512b7931ad Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
 "257 patches.

  Subsystems affected by this patch series: scripts, ocfs2, vfs, and
  mm (slab-generic, slab, slub, kconfig, dax, kasan, debug, pagecache,
  gup, swap, memcg, pagemap, mprotect, mremap, iomap, tracing, vmalloc,
  pagealloc, memory-failure, hugetlb, userfaultfd, vmscan, tools,
  memblock, oom-kill, hugetlbfs, migration, thp, readahead, nommu, ksm,
  vmstat, madvise, memory-hotplug, rmap, zsmalloc, highmem, zram,
  cleanups, kfence, and damon)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (257 commits)
  mm/damon: remove return value from before_terminate callback
  mm/damon: fix a few spelling mistakes in comments and a pr_debug message
  mm/damon: simplify stop mechanism
  Docs/admin-guide/mm/pagemap: wordsmith page flags descriptions
  Docs/admin-guide/mm/damon/start: simplify the content
  Docs/admin-guide/mm/damon/start: fix a wrong link
  Docs/admin-guide/mm/damon/start: fix wrong example commands
  mm/damon/dbgfs: add adaptive_targets list check before enable monitor_on
  mm/damon: remove unnecessary variable initialization
  Documentation/admin-guide/mm/damon: add a document for DAMON_RECLAIM
  mm/damon: introduce DAMON-based Reclamation (DAMON_RECLAIM)
  selftests/damon: support watermarks
  mm/damon/dbgfs: support watermarks
  mm/damon/schemes: activate schemes based on a watermarks mechanism
  tools/selftests/damon: update for regions prioritization of schemes
  mm/damon/dbgfs: support prioritization weights
  mm/damon/vaddr,paddr: support pageout prioritization
  mm/damon/schemes: prioritize regions within the quotas
  mm/damon/selftests: support schemes quotas
  mm/damon/dbgfs: support quotas of schemes
  ...
2021-11-06 14:08:17 -07:00
Marco Elver 7594b34774 kasan: common: provide can_alloc in kasan_save_stack()
Add another argument, can_alloc, to kasan_save_stack() which is passed
as-is to __stack_depot_save().

No functional change intended.

Link: https://lkml.kernel.org/r/20210913112609.2651084-5-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Tested-by: Shuah Khan <skhan@linuxfoundation.org>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Taras Madan <tarasmadan@google.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vijayanand Jitta <vjitta@codeaurora.org>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Cc: Walter Wu <walter-zh.wu@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-11-06 13:30:33 -07:00
Vincenzo Frascino 2d27e58514 kasan: Extend KASAN mode kernel parameter
Architectures supported by KASAN_HW_TAGS can provide an asymmetric mode
of execution. On an MTE enabled arm64 hw for example this can be
identified with the asymmetric tagging mode of execution. In particular,
when such a mode is present, the CPU triggers a fault on a tag mismatch
during a load operation and asynchronously updates a register when a tag
mismatch is detected during a store operation.

Extend the KASAN HW execution mode kernel command line parameter to
support asymmetric mode.

Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20211006154751.4463-6-vincenzo.frascino@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-10-07 09:30:24 +01:00
Vincenzo Frascino f5627ec1ff kasan: Remove duplicate of kasan_flag_async
After merging async mode for KASAN_HW_TAGS a duplicate of the
kasan_flag_async flag was left erroneously inside the code.

Remove the duplicate.

Note: This change does not bring functional changes to the code
base.

Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Signed-off-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20211006154751.4463-2-vincenzo.frascino@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-10-07 09:21:57 +01:00
Linus Torvalds 14726903c8 Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
 "173 patches.

  Subsystems affected by this series: ia64, ocfs2, block, and mm (debug,
  pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap,
  bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure,
  hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock,
  oom-kill, migration, ksm, percpu, vmstat, and madvise)"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits)
  mm/madvise: add MADV_WILLNEED to process_madvise()
  mm/vmstat: remove unneeded return value
  mm/vmstat: simplify the array size calculation
  mm/vmstat: correct some wrong comments
  mm/percpu,c: remove obsolete comments of pcpu_chunk_populated()
  selftests: vm: add COW time test for KSM pages
  selftests: vm: add KSM merging time test
  mm: KSM: fix data type
  selftests: vm: add KSM merging across nodes test
  selftests: vm: add KSM zero page merging test
  selftests: vm: add KSM unmerge test
  selftests: vm: add KSM merge test
  mm/migrate: correct kernel-doc notation
  mm: wire up syscall process_mrelease
  mm: introduce process_mrelease system call
  memblock: make memblock_find_in_range method private
  mm/mempolicy.c: use in_task() in mempolicy_slab_node()
  mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies
  mm/mempolicy: advertise new MPOL_PREFERRED_MANY
  mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY
  ...
2021-09-03 10:08:28 -07:00
Woody Lin c9d1af2b78 mm/kasan: move kasan.fault to mm/kasan/report.c
Move the boot parameter 'kasan.fault' from hw_tags.c to report.c, so it
can support all KASAN modes - generic, and both tag-based.

Link: https://lkml.kernel.org/r/20210713010536.3161822-1-woodylin@google.com
Signed-off-by: Woody Lin <woodylin@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-09-03 09:58:14 -07:00
Mark Rutland 7672150301 arm64: kasan: mte: remove redundant mte_report_once logic
We have special logic to suppress MTE tag check fault reporting, based
on a global `mte_report_once` and `reported` variables. These can be
used to suppress calling kasan_report() when taking a tag check fault,
but do not prevent taking the fault in the first place, nor does they
affect the way we disable tag checks upon taking a fault.

The core KASAN code already defaults to reporting a single fault, and
has a `multi_shot` control to permit reporting multiple faults. The only
place we transiently alter `mte_report_once` is in lib/test_kasan.c,
where we also the `multi_shot` state as the same time. Thus
`mte_report_once` and `reported` are redundant, and can be removed.

When a tag check fault is taken, tag checking will be disabled by
`do_tag_recovery` and must be explicitly re-enabled if desired. The test
code does this by calling kasan_enable_tagging_sync().

This patch removes the redundant mte_report_once() logic and associated
variables.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Will Deacon <will@kernel.org>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Tested-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20210714143843.56537-4-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-08-02 18:15:28 +01:00
Mark Rutland 8286824789 arm64: kasan: mte: use a constant kernel GCR_EL1 value
When KASAN_HW_TAGS is selected, KASAN is enabled at boot time, and the
hardware supports MTE, we'll initialize `kernel_gcr_excl` with a value
dependent on KASAN_TAG_MAX. While the resulting value is a constant
which depends on KASAN_TAG_MAX, we have to perform some runtime work to
generate the value, and have to read the value from memory during the
exception entry path. It would be better if we could generate this as a
constant at compile-time, and use it as such directly.

Early in boot within __cpu_setup(), we initialize GCR_EL1 to a safe
value, and later override this with the value required by KASAN. If
CONFIG_KASAN_HW_TAGS is not selected, or if KASAN is disabeld at boot
time, the kernel will not use IRG instructions, and so the initial value
of GCR_EL1 is does not matter to the kernel. Thus, we can instead have
__cpu_setup() initialize GCR_EL1 to a value consistent with
KASAN_TAG_MAX, and avoid the need to re-initialize it during hotplug and
resume form suspend.

This patch makes arem64 use a compile-time constant KERNEL_GCR_EL1
value, which is compatible with KASAN_HW_TAGS when this is selected.
This removes the need to re-initialize GCR_EL1 dynamically, and acts as
an optimization to the entry assembly, which no longer needs to load
this value from memory. The redundant initialization hooks are removed.

In order to do this, KASAN_TAG_MAX needs to be visible outside of the
core KASAN code. To do this, I've moved the KASAN_TAG_* values into
<linux/kasan-tags.h>.

There should be no functional change as a result of this patch.

Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will@kernel.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Tested-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20210714143843.56537-3-mark.rutland@arm.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-08-02 18:14:21 +01:00
Yee Lee 77a63c69ec kasan: add memzero init for unaligned size at DEBUG
Issue: when SLUB debug is on, hwtag kasan_unpoison() would overwrite the
redzone of object with unaligned size.

An additional memzero_explicit() path is added to replacing init by hwtag
instruction for those unaligned size at SLUB debug mode.

The penalty is acceptable since they are only enabled in debug mode, not
production builds.  A block of comment is added for explanation.

Link: https://lkml.kernel.org/r/20210705103229.8505-3-yee.lee@mediatek.com
Signed-off-by: Yee Lee <yee.lee@mediatek.com>
Suggested-by: Andrey Konovalov <andreyknvl@gmail.com>
Suggested-by: Marco Elver <elver@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Nicholas Tang <nicholas.tang@mediatek.com>
Cc: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-07-15 10:13:49 -07:00
Kuan-Ying Lee 7a22bdc3c4 kasan: add memory corruption identification support for hardware tag-based mode
Add memory corruption identification support for hardware tag-based mode.
We store one old free pointer tag and free backtrace instead of five
because hardware tag-based kasan only has 16 different tags.

If we store as many stacks as SW tag-based kasan does(5 stacks), there is
high probability to find the same tag in the stacks when out-of-bound
issues happened and we will mistake out-of-bound issue for use-after-free.

Link: https://lkml.kernel.org/r/20210626100931.22794-4-Kuan-Ying.Lee@mediatek.com
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Suggested-by: Marco Elver <elver@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Nicholas Tang <nicholas.tang@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:53 -07:00
Kuan-Ying Lee f06f78ab48 kasan: rename CONFIG_KASAN_SW_TAGS_IDENTIFY to CONFIG_KASAN_TAGS_IDENTIFY
Patch series "kasan: add memory corruption identification support for hw tag-based kasan", v4.

Add memory corruption identification for hardware tag-based KASAN mode.

This patch (of 3):

Rename CONFIG_KASAN_SW_TAGS_IDENTIFY to CONFIG_KASAN_TAGS_IDENTIFY in
order to be compatible with hardware tag-based mode.

Link: https://lkml.kernel.org/r/20210626100931.22794-1-Kuan-Ying.Lee@mediatek.com
Link: https://lkml.kernel.org/r/20210626100931.22794-2-Kuan-Ying.Lee@mediatek.com
Signed-off-by: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Suggested-by: Marco Elver <elver@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Cc: Chinwen Chang <chinwen.chang@mediatek.com>
Cc: Nicholas Tang <nicholas.tang@mediatek.com>
Cc: Kuan-Ying Lee <Kuan-Ying.Lee@mediatek.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:53 -07:00
Daniel Axtens af3751f3c2 kasan: allow architectures to provide an outline readiness check
Allow architectures to define a kasan_arch_is_ready() hook that bails out
of any function that's about to touch the shadow unless the arch says that
it is ready for the memory to be accessed.  This is fairly uninvasive and
should have a negligible performance penalty.

This will only work in outline mode, so an arch must specify
ARCH_DISABLE_KASAN_INLINE if it requires this.

Link: https://lkml.kernel.org/r/20210624034050.511391-3-dja@axtens.net
Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Marco Elver <elver@google.com>
Suggested-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-06-29 10:53:53 -07:00
Ingo Molnar f0953a1bba mm: fix typos in comments
Fix ~94 single-word typos in locking code comments, plus a few
very obvious grammar mistakes.

Link: https://lkml.kernel.org/r/20210322212624.GA1963421@gmail.com
Link: https://lore.kernel.org/r/20210322205203.GB1959563@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Reviewed-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Bhaskar Chowdhury <unixbhaskar@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-05-07 00:26:35 -07:00
Walter Wu 23f61f0fe1 kasan: record task_work_add() call stack
Why record task_work_add() call stack?  Syzbot reports many use-after-free
issues for task_work, see [1].  After seeing the free stack and the
current auxiliary stack, we think they are useless, we don't know where
the work was registered.  This work may be the free call stack, so we miss
the root cause and don't solve the use-after-free.

Add the task_work_add() call stack into the KASAN auxiliary stack in order
to improve KASAN reports.  It helps programmers solve use-after-free
issues.

[1]: https://groups.google.com/g/syzkaller-bugs/search?q=kasan%20use-after-free%20task_work_run

Link: https://lkml.kernel.org/r/20210316024410.19967-1-walter-zh.wu@mediatek.com
Signed-off-by: Walter Wu <walter-zh.wu@mediatek.com>
Suggested-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:42 -07:00
Andrey Konovalov aa5c219c60 kasan: init memory in kasan_(un)poison for HW_TAGS
This change adds an argument to kasan_poison() and kasan_unpoison() that
allows initializing memory along with setting the tags for HW_TAGS.

Combining setting allocation tags with memory initialization will improve
HW_TAGS KASAN performance when init_on_alloc/free is enabled.

This change doesn't integrate memory initialization with KASAN, this is
done is subsequent patches in this series.

Link: https://lkml.kernel.org/r/3054314039fa64510947e674180d675cab1b4c41.1615296150.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2021-04-30 11:20:41 -07:00